Rational Expressions, Vertical Asymptotes, and Holes
Rational Expression It is the quotient of two polynomials. A rational function is a function defined by a rational expression. Examples: Not Rational:
Find the domain: Graph it:
Find the domain: Graph it:
Find the domain: Graph it:
Find the domain: Graph it:
Vertical Asymptote If x – a is a factor of the denominator of a rational function but not a factor of the numerator, then x = a is a vertical asymptote of the graph of the function.
Find the domain: Graph it using the graphing calculator. What do you see?
Find the domain: Graph it using the graphing calculator. What do you see?
Hole (in the graph) If x – b is a factor of both the numerator and denominator of a rational function, then there is a hole in the graph of the function where x = b, unless x = b is a vertical asymptote. The exact point of the hole can be found by plugging b into the function after it has been simplified.
Find the domain and identify vertical asymptotes & holes.
Horizontal Asymptotes & Graphing
Horizontal Asymptotes Degree of numerator = Degree of denominator Degree of numerator < Degree of denominator Degree of numerator > Degree of denominator Horizontal Asymptote:
Find all asymptotes & holes & then graph: